I'd settle for a chapter in the Codex. Having all of the sign posts in one place and not subject to fallible human memory would be nice. Although, as I think about it, that probably won't happen. The room itself and the contents are oftentimes part of the message, an that would be hard to capture in the Codex. For example, there's one room where it's implied that the Thralls were originally created/summoned by the same spell that wrecked the northern empire, but most of that information comes from the events that happen in the room, not the sign itself.

A chapter in the codex would really be great, no matter how improbable (considering they don't even have a monsters section, it seems rather unlikely). Also, if you are going to make a lore token, it should be guaranteed an unread sign (and it restarts once you have read all in that area).